The present disclosure relates, in general, to safety door switch apparatus.
Manufacturing facilities utilize numerous automatic equipment, programmed robots, etc., to perform manufacturing tasks. This equipment poses a significant hazard to nearby workers or maintenance personnel, particularly if the equipment begins operation when a worker is performing maintenance on or working or otherwise located in proximity to the equipment.
Some manufacturing equipment is divided into work cells covering a predetermined length of a manufacturing assembly line or as stand-alone equipment. Access to the work cell can be controlled by means of a stationary fence or barrier and a sliding or swinging door which allows access to the equipment within the work cell. Such safety doors are normally latched in a closed position. Safety switches mounted on the door and the adjacent stationary fence or barrier provide a signal to the machine control that the door is closed. This signal is required in order to operate the machinery in the work cell. When a worker needs to access the machinery, they open the door which discontinues the signal to the machine control thereby deactivating the machinery for the safety of the worker.
Prior safety switch apparatus prevent the closing and re-latching of the door to the fence when a worker is inside of the work cell by preventing a pivotal handle carrying part of the switch apparatus from advancing into the normal door closed and handle latched position. Manually operated padlocks carried by the workers can be inserted into the safety apparatus to prevent the door handle from being latching in the closed position which would cause the machinery to reactive while the worker is still in the work cell.
However, the available safety door switch apparatuses require special components which makes it difficult to obtain such safety door switch apparatus in a timely manner when needed in a manufacturing facility. It would be desirable to provide a safety door switch apparatus made from simple and easy to make and procure components, and including simple mechanical bracketing.